Fluid transformer

ABSTRACT

A JET PUMP OR FLUID TRANSFORMER HAVING A HOUSING OF GENERALLY STRAIGHT-THROUGH TUBULAR FORM AND INCLUDING A SUCTION END PORTION AND A FLUID DISCHARGE END PORTION, AND FLUID JET INPUT MEANS COMMUNICATING WITH THE INTERIOR OF THE HOUSING AT A POSITION INTERMEDIATE OPPOSED ENDS THEREOF TO DELIVER AND TO DISCHARGE IMPELLING FLUID UNDER PRESSURE INTO THE HOUSING, THE HOUSING BEING CHARACTERIZED IN THAT IS CARRIES ON AN INSIDE WALL THEREOF DOWNSTREAM OF SAID FLUID JET INPUT MEANS A PLURALITY OF RADIALLY INWARDLY DISPLACED ANNULAR BANDS, RING, FLANGES, OR FACETS SPACED LINEALLY ALONG THE HOUSING, THE RINGS AS VIEWED IN CROSS SECTION EXTENDING IN PLANES GENERALLY NORMAL TO A LONGITUDINAL AXIS OF THE HOUSING AND DEFINING FLUID FLOW ABUTMENT OR ENTRAINMENT ELEMENTS EFFECTIVE TO ORIENT FLOW PATTERNS AND PHYSICAL DISTRIBUTION OF FLUID MOLECULES IMPINGING THEREAGAINST, THEREBY TO ENCHANCE THE FLUID WALL BOUNDARY FLOW RATE AND TO PROVIDE IMPROVED OVERALL PUMPING EFFICIENCY.

May 23, 19372 w. T. MAYS EI'AL 3,664,768

FLUID TRANSFORMER mind March 10, 1970 2 sheets-sheet 1 46 80 /38 A 34 66 56 i ua ANGLE OF IMPACT l INDUCED FLOWS DEPENDENT UPON INPUT ANGLE-VELOCITY-VOLUME L /////fl [FLUID INTRODUCTION/P/OTNT/ 7 EXTERNAL JET PRINCIPLE FLOW PRESSURE MOLECULAR DISTORTION AND W G 59 A OF //////////4/ INDUCED FLOW FLOWS DEPENDENT UPON INVENTORS.

INPUT DISTORTION- VELOCITY-VOLUME WILL/AM I'M/1K9 JOHN C. MAYS y///// u |6 I/NTNO/DUC/TION TINT w TRANSFORMER PRINCIPLE May 23, 1972 w, -r MAYS ETAL 3,664,768

FLUID TRANSFORMER Fiied March 10, 1970 2 Sheets-Sheet 2 United States Patent 3,664,768 FLUID TRANSFORMER William T. Mays, Indian River County (283 6th Ave. SW., Vero Beach, Fla. 32960), and John C. Mays, Citrus County, Fla. (Box 476, Homosassa Springs, Fla.

Filed Mar. 10, 1970, Ser. No. 18,212 Int. Cl. FiMf /46 US. Cl. 417-197 12 Claims ABSTRACT OF THE DISCLOSURE A jet pump or fluid transformer having a housing of generally straight-through tubular form and including a suction end portion and a fluid discharge end portion, and fluid jet input means communicating with the interior Of the housing at a position intermediate opposed ends thereof to deliver and to discharge impelling fluid under pressure into the housing, the housing being characterized in that it carries on an inside wall thereof downstream of said fluid jet input means a plurality of radially inwardly displaced annular bands, rings, flanges, or facets spaced lineally along the housing, the rings as viewed in cross section extending in planes generally normal to a longitudinal axis of the housing and defining fluid flow abutment or entrainment elements effective to orient flow patterns and physical distribution of fluid molecules impinging thereagainst, thereby to enhance the fluid wall boundary flow rate and to provide impoved overall pumping efliciency.

The present invention relates to a jet pump or fluid transformer. More particularly, the invention is directed to an improved jet-actuated tubular pump of the type in which the fluid flow impelling jet is introduced into the pump housing through an annular duct or orifice as contrasted with a centrally disposed or axially extending tube or pipe.

It is a significant feature of the fluid transformer of the invention that it operates at greatly improved efliciency and effectiveness with a minimum of turbulence and that the improvements realized are accomplished through a structural modification of the pump housing, which modification may appear to be relatively simple in nature but which is unobvious and results in unexpected and highly desirable benefits not heretofore achieved,

Many types of jet actuated pumps and related devices for effecting and augmenting the momentum and increasing the volume rate of fluid flow are known in the prior art, and these devices have taken diverse and greatly varied physical forms. Numerous structural materials have been used. Fundamental and basic physical and hydraulic principles have been invoked and applied, with greater or lesser successes. However, in each case one or more deficiencies or objectionable features have persisted, and no prior art structure has proven completely satisfactory for even reasonably limited industrial applications.

Widely used internal jet pumps or injectors in which a fast moving, impelling fluid or jet is introduced at relatively high pressure into the center portion of a tube or housing, the jet being encircled with a conveyed or an induced fluid, are objectionable in that they are inherently unsuited to straight pass through of solid objects which may be carried by the conveyed fluid. In many instances the design parameters of such pumps are exceedingly critical, particularly for high capacity units. In internal jet pumps fluid flow instabilities occur due to the formation of a boundary layer of slowly moving fluid within the diffuser or discharge portion of the apparatus. Similar difficulties exist in external jet pumps, but to lesser extents.

3,664,768 Patented May 23, 1972 "ice Fluid injection pumps in which the impelling fluid stream or jet is introduced on the outside of the conveyed or induced fluid, such pumps being referred to as external jet pumps are ordinarily reasonably eflicient but are unusually and objectionably sensitive to the angle of discharge of the nozzle or the jet. Pumps of this general type require relatively high nozzle velocities. Moreover, the large cross sectional area of the jet itself results in orifices in which wall clearances are limited and, therefore, subject to blockage by even small stream-carried particles present in the inducing fluid. However, solids carried by the conveyed fluid pass easily through the pumps. It is to the solution of the above and other short comings of prior art fluid injection pumps that the subject invention is aimed.

It is a principal object of the present invention to provide an improved jet-actuated pump operable at high efliciency over a wide range of pressures and in which fluid boundary wall flow is increased.

A related object of the invention is to provide a jetactuated fluid pump in which the principle of entrainment areas or wall surface contours is eflectively applied to increase boundary flow velowity both upstream and downstream of the impelling jet input.

Yet another object of the invention is to provide a jet actuated pump or fluid transformer in which jet or nozzle velocities are less critical than in many prior art devices.

Still another object of the invention is to provide a jet-actuated pump which will operate efficiently and effectively when used with materials varying widely in viscosity and whose functioning will not be impared by foreign matter or solids contained in any operating system involved.

It is a general object to provide a jet-actuated fluid transformer or pump of the straight through type which will discharge a fluid stream under conditions of stability, minimum turbulence, wide capacity range, simple construction and improved overall efliciency.

It is a principal feature of the fluid transformer of the invention that many of the advantages achieved are related to or result from the incorporataion of special wall contours or entrainment rings or bands on an inner wall face of the tubular pump housing.

Other and further objects, features, and advantages of the invention will become apparent upon a consideration of the following description of several forms of the invention when read in conjunction with the drawings in which:

FIG. 1 is a vertical cross sectional view of a fluid transformer or jet pump embodying features of this in vention and inculding a plurality of decreasing diameter stepped entrainment elements or contours formed in the pump housing:

FIG. 2 is a .vertical cross-sectional view of a second embodiment of the fluid transformer of the invention with small entrainment steps adjacent to the jet input;

FIG. 3 is an exploded cross-sectional view of a two component embodiment of the invention and illustrating the use of entrainment steps in an impelling fluid annular input chamber as well as an array of ring-like stepped entrainment elements of successively reduced diameter formed in the housing wall downstream from the point of injection of the flow inducing or impelling fluid;

FIG. 4 is a sketch illustrating diagrammatically some of the physical principles believed to be relevant to a better understanding of the manner in which the advantages and improved fluid flow efficiency of the present invention are achieved, and

FIG. 5 is a cross-sectional view similar to that shown in FIG. 3 but with the two component parts of the fluid transformer assembled in an operating disposition.

In accordance with the practice of the present invention the aims and advantages achieved in devices of kind described and illustrated are realized by and attributable to the incorporation in or to the formation at an inner fluid-directing and guiding wall of the housing of contoured annular ring portions or facets against which fluid traveling through the housing impinges whereby fluid flow characteristics through the pump are materially enhanced. The rings or facets may be one or more in number and may be positioned at various selectable positions along the axial expanse of the tubular housing, all in accordance with the teachings of the invention.

In the drawings several forms of the invention, incorporating the novel features thereof, are shown for illustrative purposes. In each of the three different structures depicted, fluid throughput or travel of induced fluid is from left to right. In each example the input jet or inducing fluid is introduced at a point along the tubular housing intermediate the opposed ends thereof. Also, in each case illustrated, the impelling fluid enters the principal passage or tubular housing at an annular duct or orifice opening in a direction facing the exhaust end of the housing.

Referring now more particularly to the drawings and first to FIG. 1, one preferred embodiment of the invention there illustrated comprises a jet-actuated pump or fluid transformer including a generally tubular casing or housing 22 which is shown as consisting of two intercoupled, mechanically joined or secured coaxial sections 28 and 30. Any preferred means such as bolts, adhesives, threads, and friction fitting may be used to retain the sections together. Many structural materials including metals and plastics may be used, as dictated by the intended utility. The tubular housing 22 is open at each end, the opening at the left end being the fluid inlet port 34 or suction end and the right end being the exhaust port 38 or fluid discharge end so that in the pumping operation the impelling fluid induces fluid flow from left to right.

The housing wall 42 is provided with a bore 44 extending from the outer surface 46 into the wall and communicating with an annular cavity or channel 50 formed in the wall of the housing 22. As shown, the bore 44 is tapped 46 to facilitate connection to a line 54 supplying an impelling fluid to the pump 20. At its forward or downstream end the channel 50 communicates through a relatively restricted passageway duct or annular slot or orifice 56 with the interior 60 of the housing. The radially spaced wall elements 64 and 66 which define and form the orifice 56 constitute fluid injection or nozzle means forcibly directing an annular stream of impelling fluid (not shown) into the interior of the housing 22 and along the interior wall surface 70.

As shown in the cross sectional view of FIG. 1, the wall 42 of the housing 20 is formed, beginning at the orifice 56 and extending downstream thereof, with an array or plurality of annular steps or rings 74 extending lineally along a longitudinal axis of the housing, cross sections of said rings defining planes extending normally of the housing axis. In the particular embodiment of the fluid transformer depicted the rings 74 are of successively reduced diameter, as viewed in the direction of flow of fluid through the housing or casing passage 60. Each ring 74 is joined to the ring there adjacent by a forwardly and inwardly directing segment wall facet 80. The arrangement described establishes frustoconical fluid abutment structures on the internal boundary wall of the housing 20, giving in the cross sectional view of FIG. 1, a modified sawtooth-like configuration.

In practicing the present invention it has been found that the stepped structure described above serves as fluid flow orientation means operative materially to increase fluid wall boundary flow rates and to provide more elfective entrainment of molecules from the center or core portion of the casing 20 thereby establishing more eflicient and effective pumping action and fluid through flow and transport.

It has proven helpful to a better understanding of the present invention to theorize that the stepped narrowing of the fluid passageway and the concurrent forced movement of fluid molecules through the successive stages of reduced cross sectional area causes, in accordance with an equilibrium principle paralleling the Le Chatelier effect, fluid flow orientation, not only in the gross sense, but more fundamental molecular effects as well. For example, it is the inventors conception that the physical forces established and operating in the mechanical structure described may be effective to alter to some extent even the physical shapes of the fluid molecules in the stressed system. Thus the establishment of elongated, generally cylindrically shaped molecules would provide a physical contour permitting closer physical packing and enhancement of axial movement forwardly through the pump housing. The principle suggested above is illustrated diagrammatically in FIG. 4 of the drawing. It is appreciated that further research may be necessary fully to confirm, or even to provide grounds to refute, the thesis proposed. In any case, the experience with and documented performance records of fluid transformers fabricated in accordance with the present invention attest to the excellent results obtained-irrespective of whatever laws of physics or molecular behavior may be involved.

A second, and in some respects a somewhat simplified form of a fluid injection pump in accordance with the present invention is shown in FIG. 2. It is in many features similar to the first embodiment, different primarily in the location and general distribution of the annular rings, facets, or fluid flow interruption means. The pump of FIG. 2 includes a generally tubular housing or casing 122 including an input section 128 and an exhaust section 130, the sections being coaxial and secured to one another in a fluid-tight connection. The housing has an axially extending fluid conducting passageway 132 with an outwardly flaring fluid inlet port 134 at the left end and a fluid exhaust or discharge port 136 at the right end. The housing wall 142 is provided with a bore or port 144 extending inwardly of the wall from an outer surface 146 thereof and communicating with an annular channel 150 formed in the wall of the housing. Impelling fluid is introduced into the pump through the port 144 and the channel 150, the latter communicating with the central passageway 132 through a constructed annular duct 156. The forward wall or face of the input jet defining structure is rounded somewhat and, as shown, preferably is formed with angled steps which establish entrainment or induction means increasing the boundary flow rate at the impelling fluid injection nozzle 156. Two or more tapered steps may be provided in the wall of the pump housing downstream of the nozzle exhaust, the positioning and spacing being dictated by factors such as flow velocity, pressure, and tube cross sectional area. In the particular preferred example of FIG. 2 the nozzledefining elements are machined or otherwise formed to direct the high velocity impelling fluid input stream slightly inwardly, at an angle of approximately twelve degrees (12).

An axially exploded view of still another embodiment of the invention is shown in FIG. 3. While differing somewhat in physical form from the examples previously described, it invokes the same principles. Conveniently manufactured as a two-piece structure, the pump 200 of FIG. 3 includes what may be referred to as input section 210 and an exhaust section 220 means being provided to interconnect the sections axially, as clearly indicated. Any securement technique may be employed, one such technique being illustrated as threaded bolts 224 and 228 extending through bores 232 and 234 in the wall 240 of the input section 210 and secured in cooperating, aligned tapped bores 246 and 248 provided in the wall 260 of the exhaust section 220 of the pump 200.

The two sections 210 and 220 are formed to define coaxial generally tubular through fluid passageways 264 and 268, the entrance and the exit to each being flared outwardly. The forwardly extending wall element 272 of the input section 210 merits special consideration. As shown, the wall 272 is formed with a plurality of radial steps 280 spaced axially along the outer or bounding linearly extending surface thereof. At its forward end the wall 272 terminates in an annular flange 292 which, upon assembly of the unit, becomes a part of the structure defining the fluid injection orifice in cooperation which a coaxial encircling inside wall portion 296 of the exhaust section 220.

Upon consideration of the exploded view, it will be appreciated that, upon assembly of the two components, there will be formed a fluid transformer having the general form of the pump of FIG. 1, but with some additional features. With the structure of FIG. 3 assembled, the forward edge portion 292 of the input section 210 will come to rest near the inward end 296 of the flared input of the exhaust section, as the end flange 310 of the input section 210 seats in the annular end groove 314 of the exhaust section 220.

The wall 260 of the exhaust portion 220 of the pump 200 is provided with a tapped bore 330 extending inwardly from the outside wall surface 332 and communicating through a passage 340 to an annular cavity 350 formed between the left side end wall 352 of the exhaust section and an opposed annular wall element 360 of the fluid input or suction section 210. The annular cavity 350 communicates in turn through an anular, irregular passage, formed between facing surfaces of the forwardly extending wall portion 272 of the suction section 210 and the flared entrance wall 370 of the exhaust section 220. The passage will terminate, at its forward end, in an annular fluid injection orifice correlated with the clearance between flange 292 and the Wall 370.

Immediately downstream of the impelling fluid injectionorifice the inside wall surface, the pump section 220, is formed to provide a plurality of tapered steps consisting of annular ring-like facets 380 forming a wall surface with surface discontinuities. As shown, successive rings have reduced cross sectional areas, in the direction of flow of discharge fluid through the pump housing. As previously described, the effect achieved is to increase fluid wall boundary flow and pumping efficiency.

In addition to the entrainment steps or contours 380 downstream of the jet, pump of FIG. 3 has improved flow inducement resulting from the use of stepped wall elements 280 located upstream of the annular fluid discharge jet or duct.

It is believed that from the foregoing description the general operation of the pumps of this invention will be readily understood by those skilled in the relevant art. Briefly, fluid under pressure is introduced through the port in the housing wall. The fluid is carried to and is discharged through the relatively constricted annular duct. The fluid, as directed by the formation of the duct, advances forwardly at a relatively high velocity. The fluid flows on the stepped wall and the flow creates a lower pressure on the suction or intake side of the pump. The resultant pressure differential extending axially of the pump housing provides a controlled fluid flow through the housing, from intake to exhaust.

A fuller appreciation of the improvements inherent in the fluid transformers of the present invention will be had upon consideration of the performance characteristics of several examples. Using a regular water supply /2" hose at 40 lbs. pressure) a given container was consistently' filled in 25 seconds. The time for emptying this container using a jet pump with no entrainment units was 30 to 40 seconds. Using the same power source, the time for emptying the same container using the same size pump in which simple entrainment elements have been incorporated was only 18 seconds. With additional entrainment steps, the same container was emptied in 11 seconds, or at three to almost four times the rate established for the conventional jet-actuated pump.

As there seems to be a relationship between flow velocity through the jet nozzle and the specific entrainment design used, units of the present invention may be constructed to meet special requirements. In general the lower the jet velocity, the larger the step contour, the lower will be the pressure, but the greater the flow. Thus in,the fluid transformers of the invention it is possible to use fluids at highpressure potential with small flow rates and convert to low pressure potentials with large flows.

The structural configurations of the jet-actuated fluid pumps of the present invention are most versatile and are valuable and effective for many different types of industrial applications. They may be fabricated in both small and large capacity modelsall with comparable high efliciencies. The units will handle materials covering an extremely broad range of viscosities, and the straightthrough or pass through arrangement permits the pump to move all types of fluids, slurries, mud and fluid-transported stones as well as other solids. The pumps will operate at low potentials (20 pounds or less) as well as at high pressure. There are no moving mechanical parts and wear characteristics are excellent. Construction is extremely simple and there is essentially no jet stoppage and no need for priming.

Typical uses for the improved jet actuated pump of the invention are in dredging operations, fluid propulsion, sump pumps, pool circulators, oil line booster units, high pressure power units, mixing devices, switching devices and carburetors.

What is claimed is:

1. A pump devoid of moving mechanical parts and operative through regulated liquid injection jet action correlated with a liquid flow controlling guide means including a physically contoured configuration of a liquid directing principal passageway of said pump to guide and to discharge a liquid stream under conditions of high stability, minimum turbulence, and improved overall pumping efi'iciency,

said pump comprising, in combination,

a generally straight-through tubular housing having a suction end and an exhaust end at opposed axially displaced extremities of said housing,

said housing including a liquid inlet port at said suction end a liquid discharge port at said exhaust end, and

liquid input means,

said liquid input means comprising a passage extending through a bounding tubular wall of said housing at a position intermediate said opposed extremities thereof and communicating with the interior of said housing through a generally annular liquid injection nozzle coaxial with said housing,

said nozzle terminating in an annular duct-like orifice facing and directed toward said exhaust end of said housing,

an inner wall face of said bounding wall of said housing being formed to define liquid flow orienting means,

said liquid flow orienting means comprising passageway constriction means in said tubular housing, said constriction means defining a succession of radially inwardly stepped wall segments of said tubular housing,

said liquid flow orienting means comprising passageway constriction means in said tubular housing, said constriction means defining a plurality of successive annular wall segments,

said successive wall segments spaced in a fluid flow direction from said orifice toward said exhaust end of said housing defining in conjunction with interconnecting annular wall sections therebetweena linear array of rings constituting a series of unidirectionally radially inwardly stepped wall segments establishing within said housing axially spaced zones exhibiting 7 ever decreasing cross-sectional areas correlated with successive said wall segments disposed along said principal passageway of said housing.

2. A pump as set forth in claim 1 wherein said wall segments comprise a plurality of annular wall segments projecting generally radially inwardly of said inner wall face of said housing and spaced axially therealong, and wherein at least one of said annular wall segments is chamfered to provide a forwardly and inwardly converging fluid particle engaging and orienting surface element.

3. A pump as set forth in claim 1 wherein said wall segments comprise a series of discrete annular bands defining a portion of an inside wall of said tubular housing, said series extending as a finite array along a longitudinal axis of said housing and constituting surface interruption means establishing multiple distinct, annular surface facets on the inside wall of said housing.

4. The structure as set forth in claim 3 wherein at least one of said facets is flared into a generally frusto conical configuration, and projects forwardly and inwardly as viewed in a direction toward said exhaust end of said tubular housing.

5. The structure as set forth in claim 1 wherein said housing is circular in cross section, and wherein at least some of said radially inwardly stepped wall segments are greater in cross sectional diameter than are other wall segments located downstream thereof.

6. The structure as set forth in claim 1 wherein said radially displaced annular wall segments are displaced inwardly of a principal inner wall surface of said housing.

7. In a pump devoid of moving mechanical parts and operative through regulated fluid injection jet action correlated with a fluid flow guide means including a physically contoured configuration of a fluid-directing principal passageway of said pump to impel, guide and to discharge a fluid stream under conditions of high stability, minimum turbulence, and improved overall pumping efficiency,

said pump including, in combination,

a generally straight-through tubular housing having a fluid suction end and a fluid exhaust end at opposed axially displaced extremities of said housing,

said housing including,

a fluid inlet port at said suction end,

'a fluid discharge port at said exhaust end, and

impeller fluid input means,

said impeller fluid input means comprising a passage extending through a bounding tubular wall of said housing at a position intermediate said opposed extremities thereof and communicating with the interior of said housing through a generally annular fluid injection nozzle coaxial with said housing,

said nozzle terminating in an annular duct-like orifice facing and directed toward said exhaust end of said housing,

the improvement comprising fluid flow orienting means,

said fluid flow orienting means comprising a plurality of discrete radially displaced annular wall segments formed on an inner wall face of said bounding wall of said housing,

at least one of said wall segments being formed on an inner wall face of said bounding wall of said housing,

said liquid flow orienting means comprising passageway constriction means in said tubular housing, said constriction means defining a plurality of successive annular wall segments,

said successive wall segments spaced in a fluid flow direction from said orifice toward said exhaust end of said housing defining in conjunction with interconnecting annular Wall sections therebetween a linear array of rings constituting a series of unidirectionally radially inwardly stepped wall segments establishing within said housing axially spaced zones exhibiting ever decreasing cross-sectional areas correlated with successive said wall segments disposed along said principal passageway of said housing.

8. The improvement as set forth in claim 2 wherein at least one of said wall segments is a radially inwardly displaced annular wall segmet formed on an inner Wall face of said bounding wall of said housing downstream '0 said fluid injection nozzle.

9. The improvement as set forth in claim 2 wherein at least one of said wall segments comprises a radially displaced annular wall segment formed on an inner wall face of said bounding wall of said housing upstream of said fluid injection nozzle.

10. In a pump devoid of moving mechanical parts and operative through regulated fluid injection jet action correlated with a fluid flow guide means including a physically contoured configuration of a fluid-directing principal passageway of said pump to impel, guide and to discharge a fluid stream under conditions of high stability, minimum turbulence, and improved overall pumping efl'iciency,

said pump including, in combination,

a generally straight-through tubular housing having a fluid suction end and a fluid exhaust end at opposed axially displaced extremities of said housing,

said housing including,

a fluid inlet port at said suction end,

a fluid discharge port at said exhaust end, and

impeller fluid input means,

said impeller fluid input means comprising a passage extending through a bounding tubular wall of said housing at a position intermediate opposed said extremities thereof and communicating with the interior of said housing through a generally annular fluid injection nozzle coaxial with said housing,

said nozzle terminating in an annular duct-like orifice facing and directing toward said exhaust end of said housing,

the improvement comprising fluid flow orienting means,

said fluid flow orienting means comprising a plurality of discrete radially displaced annular wall segments formed on an inner wall face of said bounding wall of said housing,

atleast one of said wall segments comprising a radially displaced annular wall segment formed on an inner wall face of said bounding wall of said housing upstream of said fluid injection nozzle.

11. A pump devoid of moving mechanical parts and operative through regulated liquid injection jet action correlated with a liquid flow controlling guide means including a physically contoured configuration of a liquid directing principal passageway of said pump to guide and to discharge a liquid stream under conditions of high stability, minimum turbulence, and improved overall pumping efficiency,

said pump comprising, in combination,

a generally straight-through tubular housing having a suction end and an exhaust end at opposed axially displaced extremities of said housing,

said housing including,

a liquid inlet port at said suction end,

a liquids discharge port at said exhaust end, and

liquid input means,

said liquid input means comprising a passage extending through a bounding tubular wall of said housing at a position intermediate opposed. said extremities thereof and communicating with the interior of said housing through a generally annular liquid injection nozzle coaxial with said housing,

said nozzle terminating in an annular duct-like orifice facing and directed toward said exhaust end of said housing,

an inner wall face of said bounding wall of said housing being formed to define liquid flow orienting means,

said liquid flow orienting means comprising passageway constriction means in said tubular housing, said constriction means defining a succession of radially inwardly stepped wall segments of said tubular housing, constituting wall portions thereof,

said liquid flow orienting means comprising passageway constriction means in said tubular housing, said constriction means defining a flow passage having a transverse sectional profile that progressively decreases in the direction of flow,

said passage only decreasing in transverse cross-section at any point of change in said profile and being defined by a plurality of successive annular wall segments,

said plurality of successive wall segments including a plurality of cylindrical wall segments spaced apart in the fluid flow direction and a plurality of intermediate wall segments that interconnect said cylindrical segments.

12. In a pump devoid of moving mechanical parts and operative through regulated fluid injection jet action correlated with a fluid flow guide means including a physically contoured configuration of a fluid-directing principal passageway of said pump to impel, guide and to discharge a fluid stream under conditions of high stability, minimum turbulence, and improved overall pumping efficiency,

said pump including, in combination,

a generally straight-through tubular housing having a fluid suction end and a fluid exhaust end at opposed axially displaced extremities of said housing,

said housing including,

a fluid inlet port at said suction end, 1

a fluid discharge port at said exhaust end, and

impeller fluid input means,

said impeller fluid input means comprising a passage extending through a bounding tubular wall of said housing at a position intermediate opposed said extremities thereof and communicating with the interior of said housing through a generally annular fluid injection nozzle coaxial with said housing,

said nozzle terminating in an annular duct-like orifice facing and directed toward said exhaust end of said housing,

the improvement comprising fluid flow orienting means,

said fluid flow orienting means comprising a plurality of discrete radially displaced annular wall segments formed on an inner wall face of said bounding wall of said housing,

said liquid flow orienting means comprising passageway constriction means in said tubular housing, said constriction means defining a flow passage having a transverse sectional profile that progressively decreases in the direction of flow,

said passage only decreasing in transverse cross section at any point of change in said profile and being defined by a plurality of successive annular wall segments,

said plurality of successive wall segments including a plurality of cylindrical wall segments spaced apart in the fluid flow direction and a plurality of intermediate wall segments that interconnect said cylindrical segments.

References Cited UNITED STATES PATENTS 2,396,290 3/1946 Schwarz 417--197 X 2,990,103 6/1961 Coanda et al 417197 3,031,1127 4/1962 Duhaime et al. 417-198 CARLTON R. CROYLE, Primary Examiner R. E. GLUCK, Assistant Examiner US. Cl. X.R. 4l7-198 

